Yesterday, we got to check out some regulatory paperwork that seemed to reveal the presence of two upcoming Nokia Lumia smartphones, the 720 and 520. At the time, the only info we had heard about the specifics of these models is that they’d be Windows Phone 8 devices, and have hardware similar to the 710 and 510. Well, Windows Phone 8 isn’t going to agree very well with the 510’s meager 256MB of RAM, so clearly some changes would need to take place. Today, we get our first sense of just what those changes may be, with some rumored specs for both models.

Supposedly, the Lumia 520 will get a four-inch screen that would be extra touch-sensitive, like the Lumia 920’s. The phone would run a dual-core 1GHz SoC, get 512MB of RAM, and come with 8GB storage, expandable via microSD. While there would be a five-megapixel camera around back, the phone would lack a front-facer.

The Lumia 720, on the other hand, would go with a 4.3-inch Nokia Clear Black Display, but feature the same SoC, RAM, and storage specs as the 520. According to this source, it would have a six-megapixel main camera, as well as a two-megapixel front camera.

As we heard before, both phones would be Windows Phone 8 models.

We have no way to know just how accurate this information might be, so don’t hold it as gospel until we get something in the way of confirmation.